[dpdk-dev] [PATCH] net/ixgbe: align setting MTU behavior with i40e

[Beilei Xing]

Currently, setting MTU will fail if MTU requires the support
of scattered packets before scatter is enabled.
To align with i40e, this patch allows this MTU setting when
device is stopped.

Signed-off-by: Beilei Xing <beilei.xing at intel.com>
---
 drivers/net/ixgbe/ixgbe_ethdev.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c b/drivers/net/ixgbe/ixgbe_ethdev.c
index 830bbcb..60881d8 100644
--- a/drivers/net/ixgbe/ixgbe_ethdev.c
+++ b/drivers/net/ixgbe/ixgbe_ethdev.c
@@ -4811,6 +4811,7 @@ ixgbe_dev_mtu_set(struct rte_eth_dev *dev, uint16_t mtu)
 	struct rte_eth_dev_info dev_info;
 	uint32_t frame_size = mtu + ETHER_HDR_LEN + ETHER_CRC_LEN;
 	struct rte_eth_rxmode *rx_conf = &dev->data->dev_conf.rxmode;
+	struct rte_eth_dev_data *dev_data = dev->data;
 
 	ixgbe_dev_info_get(dev, &dev_info);
 
@@ -4818,13 +4819,15 @@ ixgbe_dev_mtu_set(struct rte_eth_dev *dev, uint16_t mtu)
 	if ((mtu < ETHER_MIN_MTU) || (frame_size > dev_info.max_rx_pktlen))
 		return -EINVAL;
 
-	/* refuse mtu that requires the support of scattered packets when this
-	 * feature has not been enabled before.
+	/* if device is started, refuse mtu that requires the support of
+	 * scattered packets when this feature has not been enabled before.
 	 */
-	if (!rx_conf->enable_scatter &&
+	if (dev_data->dev_started && !rx_conf->enable_scatter &&
 	    (frame_size + 2 * IXGBE_VLAN_TAG_SIZE >
-	     dev->data->min_rx_buf_size - RTE_PKTMBUF_HEADROOM))
+	     dev->data->min_rx_buf_size - RTE_PKTMBUF_HEADROOM)) {
+		PMD_INIT_LOG(ERR, "Port should be stopped first.");
 		return -EINVAL;
+	}
 
 	hw = IXGBE_DEV_PRIVATE_TO_HW(dev->data->dev_private);
 	hlreg0 = IXGBE_READ_REG(hw, IXGBE_HLREG0);
-- 
2.5.5